JP2016199183A - Steering Wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steering wheel capable of efficiently suppressing vibration transmitted from a vehicle body side and enabling component cost to be reduced.SOLUTION: A steering wheel 1 comprises: a steering wheel body 10; and an air bag module 3 attached to the steering wheel body 10. The steering wheel 1 comprises a plurality of dampers 5 which are arranged on a same circumference of a circle C having a diameter of 80 mm or more and 110 mm or less, and a resonance frequency of the air bag module 3 is made to match with a frequency of vibration transmitted from the vehicle body side.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a steering wheel that suppresses vibration transmitted from a vehicle body side.

  When vibration from the engine rotation or vibration from the road surface during travel is transmitted to the steering wheel that is fastened to the front end of the occupant side of the steering shaft, the vibration is transmitted to the driver who holds the steering wheel, causing discomfort to the driver. There was to give. Therefore, a technique for suppressing (vibrating) the vibration of the steering wheel has been conventionally proposed.

  The steering wheel described in Patent Document 1 has a pair of horn plates connected to a core metal and an airbag module, and a dynamic damper as a vibration damping mechanism is disposed between the horn plates. The dynamic damper is connected to one horn plate via an elastic body, and is configured to support the other horn plate so as to be movable in the vertical direction. When vibration having the same or close frequency as the resonance frequency unique to the dynamic damper is transmitted from the steering wheel to the dynamic damper, the dynamic damper resonates and absorbs vibration energy of the steering wheel, thereby suppressing the vibration of the steering wheel.

  The resonance frequency unique to the dynamic damper described above varies depending on the spring constant of the rubber elastic body. For example, the hardness of the rubber is adjusted in order to achieve a desired resonance frequency. For example, ethylene propylene diene rubber (EPDM) is used as the rubber material. The vibration during idling of the vehicle differs depending on the individual vehicle, but is usually in the range of 28 Hz to 39 Hz. In order to keep the resonance frequency of the dynamic damper within this range, the hardness of the EPDM rubber material needs to be extremely low. Therefore, it is difficult to adjust the hardness and cost is high.

Japanese Patent No. 5153526

  The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide a steering wheel that can effectively suppress vibration transmitted from the vehicle body side and reduce the cost of components.

  The steering wheel of the present invention is a steering wheel including a steering wheel main body and an airbag module attached to the steering wheel main body, and a plurality of dampers for damping are arranged on the same circumference. The diameter of the circle is 80 mm or more and 110 mm or less. In the steering wheel according to one aspect of the present invention, the diameter of the circle is 100 mm or less.

  In the steering wheel according to an aspect of the present invention, a plurality of shaft members are erected on the surface of the cored bar part of the steering wheel main body, and the shaft is formed on the horn plate that forms a horn switch mechanism with the cored bar part. A plurality of openings through which the member is inserted are formed, the damper is disposed between the shaft member and the opening, and the airbag module is fixed to the horn plate.

  In the steering wheel according to an aspect of the present invention, a plurality of pins protrudes from the back surface of the airbag module so as to be able to advance and retract in the protruding direction, and the pins are inserted into insertion holes formed in the cored bar portion of the steering wheel body. The airbag module is attached by inserting the distal end side, the rear end side of the pin is inserted through a guide column, and the guide column is held by the retainer of the airbag module via the damper.

  In the steering wheel according to one aspect of the present invention, the damper includes ethylene propylene diene rubber.

  According to the present invention, since the plurality of dampers for damping are arranged on the circumference of a circle having a diameter of 80 mm or more and 110 mm or less, the resonance frequency of the airbag module is set to the vibration transmitted from the vehicle body side. Vibration can be effectively suppressed according to the frequency. Further, the hardness adjustment of the rubber material of the damper becomes easy, and the cost can be reduced.

It is an exploded view of the steering wheel concerning an embodiment. It is a figure which shows the back surface of the horn plate which concerns on embodiment. It is a fragmentary sectional view of the damper concerning an embodiment. It is a figure which shows the back surface of the horn plate to which the airbag module and damper which concern on embodiment were attached. It is a disassembled perspective view of the steering wheel which concerns on another embodiment. It is a perspective view of a steering wheel concerning another embodiment. It is sectional drawing of the steering wheel at the time of the airbag module attachment which concerns on another embodiment. It is a partial expanded sectional view of the steering wheel after the airbag module attachment which concerns on another embodiment. It is a perspective view of the damper used in Example 1. FIG. It is a graph which shows the measurement result of an Example and a comparative example. It is a graph which shows the relationship between the arrangement | positioning diameter of a damper, and the resonance frequency of an airbag module.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded view of a steering wheel according to the embodiment, FIG. 2 is a view showing a back surface (surface on the cored bar side) of the horn plate, FIG. 3 is a partial sectional view of a damper, and FIG. It is a figure which shows the back surface of the horn plate to which the airbag module and the damper were attached.

  The steering wheel 1 has an airbag module 3 attached to a substantially central portion of a steering wheel body 10. The steering wheel body 10 includes a wheel part 11, a spoke part 12, a cored bar part 2, a horn plate 4, a damper 5, and a horn switch mechanism 6.

  The horn plate 4 is provided with a plurality of openings 41, and the openings 41 are inserted through the shaft member 21 erected on the surface of the cored bar 12. The damper 5 is disposed between the shaft member 21 and the opening 41. The horn switch mechanism 6 is formed between the cored bar 2 and the horn plate 4. The horn plate 4 is configured to be movable along the shaft member 21, and the airbag module 3 is fixed to the horn plate 4. The hub core part 2a of the cored bar part 2 is connected to the steering shaft.

  The airbag module 3 includes an airbag that is inflated and deployed in an emergency, an inflator 7 that supplies gas to the airbag, a retainer 31 that supports the airbag and the inflator 7, and a module that covers the airbag, the inflator 7 and the retainer 31. And a cover 32. The airbag, the inflator 7 and the module cover 32 can be arbitrarily applied with known configurations and are not limited to the illustrated shapes.

  The airbag module 3 is fixed to the horn plate 4 by a snap-in structure, for example. A claw portion 33 that is inserted into an opening 43 formed in the horn plate 4 is formed at the bottom of the retainer 31. The claw portion 33 has a shaft portion and a return portion. When the return portion is inserted into the opening 43 of the horn plate 4, the bending spring 45 disposed on the horn plate 4 is between the return portion and the bottom surface of the retainer 31. It is locked to.

  For example, as shown in FIG. 2, the horn plate 4 is composed of an annular metal plate having an opening 42 at the center. Two openings 43 are formed at the left and right positions of the flat portion of the horn plate 4. The centers of the three circular openings 41 are located on the same circumference. The claw 33 of the airbag module 3 is inserted into the opening 43, the inflator 7 of the airbag module 3 is inserted into the opening 42, and the damper 5 is disposed in the opening 41.

  A bending spring 45 is disposed so as to cross the opening 43. The bending spring 45 is composed of a metal rod formed in a substantially M shape, and is held by a projection 44a and a hook 44b so as to be slidable in the direction of the arrow in FIG.

  A snap-in structure is formed by the opening 43 and the bending spring 45. When the claw portion 33 of the airbag module 3 is inserted into the opening 43, the bending spring 45 is pushed away in the direction of the arrow and slides, and when the claw portion 33 exceeds the return portion, the bending spring 45 is restored. 33 is fixed to the horn plate 4.

  As shown in FIG. 3, the horn plate 4 is biased in a direction away from the core metal part 2 by a coil spring 46 disposed between the horn plate 4 and the core metal part 2. The coil spring 46 is locked by a resin locking portion 47 provided at the peripheral edge of the opening 41. Flange portions 47a and 47b are respectively provided on the front surface (the surface on the airbag module 3 side) and the back surface (the surface on the core metal portion 2 side) of the locking portion 47, and the flange portions 47a and 47b are provided in the opening 41. The peripheral edge of is held. A hook portion 47 c that locks the coil spring 46 is formed on the back surface of the locking portion 47.

  The cored bar portion 2 is formed with a convex portion 22 at a position where the shaft member 21 is fixed, and a bolt hole 23 is formed in the convex portion 22. The convex portion 22 is formed to ensure the length of the bolt hole 23. When the core metal part 2 has a sufficient thickness, the convex part 22 may be omitted.

  For the shaft member 21, for example, a bolt having a head on a flange is used. The shaft member 21 is erected on the cored bar portion 2 by screwing the tip end portion 21 a of the shaft member 21 into the bolt hole 23. The shaft member 21 is disposed so as to pass through the opening 41 of the horn plate 4. The coil spring 46 is disposed between the convex portion 22 of the core metal part 2 and the horn plate 4.

  The horn switch mechanism 6 is configured by the movable contact 61 disposed on the horn plate 4 and the fixed contact 62 disposed on the cored bar 2. The fixed contact 62 is fixed to, for example, the top of the convex portion 24 formed on the cored bar portion 2, and is disposed at a height that can contact the movable contact 61 by the vertical movement of the horn plate 4. The arrangement of the movable contact 61 and the fixed contact 62 is not limited to the illustrated configuration. For example, the fixed contact 62 is fixed to the surface of the cored bar 2 and the movable contact 61 is extended downward from the rear surface of the horn plate 4. You may arrange.

  The damper 5 is provided on the surface side of the substantially cylindrical body 51 and the horn plate 4 disposed between the shaft member 21 and the opening 41, and overlaps the surface of the flange portion 47 a of the locking portion 47. Part 52. The trunk | drum 51 and the collar part 52 are integrally formed. The flange portion 52 is formed in a flange shape whose entire circumference is enlarged with respect to the body portion 51. The damper 5 is preferably made of rubber having a hardness of 20 to 40, particularly about 25 to 35, according to a type A durometer in accordance with JIS K 6253. As the rubber, for example, a synthetic rubber such as ethylene propylene diene rubber or chloroprene rubber is suitable.

  A resin bush 53 is inserted into the body portion 51 of the damper 5. The bush 53 includes a shaft portion 53 a that is inserted into the body portion 51 of the damper 5, and a flange portion 53 b that is disposed on the upper surface of the flange portion 52 of the damper 5. The bush 53 prevents contact between the damper 5 and the shaft member 21 and suppresses wear of the damper 5.

  A thin annular ring-shaped elastic body 54 is inserted between the flange portion 53 b of the bush 53 and the head portion of the shaft member 21. By disposing the elastic body 54, it is possible to suppress the generation of abnormal noise caused by the shaft member 21 and the bush 53 coming into contact when the horn plate 4 is moved up and down.

  Since a locking portion 44 is provided between the horn plate 4 and the damper 5, and a bush 53 is provided between the shaft member 21 and the damper 5, it is possible to avoid contact between the damper 5 and the metal part. It is possible to suppress the wear and deterioration of the damper 5.

  By depressing the airbag module 3, the horn plate 4 moves along the shaft member 21 in the direction of the cored bar 2 (downward), and the movable contact 61 and the fixed contact 62 come into contact with each other. Blow. At this time, the damper 5, the bush 53, and the elastic body 54 disposed in the opening 41 also move along the shaft member 21 together with the horn plate 4. When the pressing force of the airbag module 3 is released, the horn plate 4 is returned to the original position by the action of the coil spring 46.

  The damper 5 functions as a dynamic damper that adjusts the vibration frequency of the airbag module 3, which is a mass body fixed to the horn plate 4, and cancels the vibration transmitted from the vehicle body side by the resonance of the airbag module 3. To do.

  As shown in FIG. 4, the dampers 5 are arranged at the same place as the opening 41, that is, at three places, and the three dampers 5 are arranged on the same circumference of the circle C. Here, the arrangement position of the damper 5 refers to the center position of the substantially cylindrical body 51 of the damper 5 and corresponds to the center position of the shaft member 21. In a state where the steering wheel 1 is viewed facing the steering wheel 1, the center of the circle C is located in the vicinity of the center of the annular wheel portion 11, in the vicinity of the center of gravity of the airbag module 3, or in an area between them. Is preferred. When the center of the wheel part 11 and the center of gravity of the airbag module 3 coincide, it is preferable that the center of the circle C is located in the vicinity thereof. The arrangement interval (distance in the circumferential direction) of the dampers 5 on the circumference of the circle C may be the same or different.

  In the present embodiment, the diameter of the circle C is preferably 80 mm or more and 110 mm or less, and particularly preferably 100 mm or less.

  In general, the diameter (width) of the airbag module 3 of the steering wheel 1 is about 160 mm, and the damper 5 is disposed on the inner side (center side) from the middle point from the center of the airbag module 3 to the end of the airbag module 3. If it is done, the air bag module 3 is likely to rattle during the horn operation, which may impair comfort. Therefore, it is preferable that the damper 5 is disposed on the outer side (end side) from the middle point from the center of the airbag module 3 to the end of the airbag module 3, and the diameter of the circle C is the diameter of the airbag module 3 ( Preferably, it is at least half of the width), that is, at least 80 mm.

  The inflator 7 inserted into the central opening 42 of the horn plate 4 is often manufactured to have a diameter of about 60 mm. The damper 5 preferably has a diameter of the flange portion 52 of 20 mm or more in consideration of the function as a dynamic damper. In order to dispose the damper 5 so as not to interfere with the inflator 7, the diameter of the circle C is preferably 80 mm or more.

  As described above, the damper 5 functions as a dynamic damper that suppresses the vibration transmitted from the vehicle body side by canceling the vibration by the resonance of the airbag module 3. The frequency of vibration transmitted from the vehicle body side has a large component of 37 to 38 Hz, and the resonance frequency of the steering wheel 1 is preferably in this band.

  The inventors have found that the resonance frequency changes according to the diameter of the circle C in which the damper 5 is disposed on the circumference thereof, and the resonance frequency decreases as the diameter of the circle C decreases. For example, the weight of the airbag module 3 is 800 to 1100 g, the damper 5 is made of rubber such as EPDM having a hardness of 25 to 35 according to a type A durometer in accordance with JIS K 6253, and the diameter (outer diameter) of the flange portion 52 is 20 mm or more. When the length of the damper 5 in the axial direction is 5 mm or more, the resonance frequency can be set to about 38 Hz by setting the diameter of the circle C to 110 mm, and the resonance frequency can be set to 100 mm by setting the diameter of the circle C to 100 mm. It can be about 37 Hz.

  Thus, according to the present embodiment, the damper 5 is arranged on the circumference of the circle C, and the resonance frequency of the airbag module 3 is determined not by the hardness of the rubber material of the damper 5 but by the diameter of the circle C. Set to the frequency of vibration transmitted from the side. Therefore, vibration transmitted from the vehicle body side can be effectively suppressed, the hardness of the rubber material of the damper 5 can be easily adjusted, and the cost can be reduced.

  Although the said embodiment demonstrated the example which arrange | positions the three dampers 5 on the periphery of the circle | round | yen C centering on the center of the wheel part 11 or the gravity center of the airbag module 3, it is not limited to this. For example, the center position of the circle C may be a position slightly deviated from the center of the wheel portion 11 or the center of gravity of the airbag module 3. Also, the upper two dampers 5 in FIG. 4 are located on the circumference of the first circle centered on the center of the wheel part 11, and the lower one damper 5 is centered on the wheel part 11. It is located on the circumference of the second circle as the center position, and the diameter of the first circle and the diameter of the second circle may be different. Also in this case, the diameter of the first circle and the diameter of the second circle are both preferably 80 mm or more and 110 mm or less, and more preferably 100 mm or less.

  In the said embodiment, the number of the opening parts 43 for which the opening part 41 for the damper 5 and the nail | claw part 33 are inserted is not limited to what is illustrated.

  The snap-in structure and the horn plate 4 are examples, and other configurations may be used. 5 to 8 are views showing a steering wheel 120 according to another embodiment. FIG. 5 is an exploded perspective view of the steering wheel 120. FIG. 6 is a perspective view of the steering wheel 120. FIG. 7 is a cross-sectional view of the steering wheel 120 when the airbag module is attached. FIG. 8 is an enlarged sectional view of a part of the steering wheel 120 after the airbag module is attached.

  The steering wheel 120 is obtained by attaching an airbag module 140 to a steering wheel main body 121. The steering wheel main body 121 has a wheel part 122, a spoke part 123, and a cored bar part 124.

  The cored bar portion 124 includes a disk-shaped airbag device mounting portion 125 (hereinafter simply referred to as “mounting portion 125”), a pin insertion hole 126 provided in the mounting portion 125, a lock spring 127, a cored bar. A steering shaft mounting hole 128 provided at the center of the portion 124 is provided.

  The lock spring 127 is substantially U-shaped, and is arranged so that one side crosses the insertion hole 126 in the chord direction. The attachment portion 125 is provided with a tunnel-shaped spring holder 130 and stoppers 131 and 132 for positioning the lock spring 127. The lock spring 127 is inserted into the spring holder 130 and positioned by contacting the stoppers 131 and 132, and as described above, the lock spring 127 is attached to the attachment portion 125 so that one side crosses the insertion hole 126 in the chord direction.

  The airbag module 140 includes a retainer 141, an inflator 142 and an airbag 143 attached to the retainer 141, a module cover 144 covering the airbag 143, and a plurality of ( In this embodiment, there are three pins 145, a horn plate 148, and the like. This pin 145 is inserted into the insertion hole 126.

  The airbag 143 is folded and attached to the retainer 141 with a bolt 146 together with the inflator 142. When the inflator 142 ejects gas at the time of a vehicle collision, the airbag 143 is inflated, and the module cover 144 is opened and deployed.

  The pin 145 is mounted in the pin holding hole 147 of the retainer 141. The pin 145 includes a pin front 150 and a pin rear 151.

  The pin rear 151 has a cylindrical portion 151a and a flange portion 151b. A female screw is provided on the inner peripheral surface of the cylindrical portion 151a. A horn switch contact tip 152 is screwed onto the female screw. In the airbag module 140, a projection 148 t is provided on the horn plate 148 so as to face the contact chip 152. The horn plate 148 is fixed to the retainer 141 with bolts 146. When the airbag module 140 is pushed and retracted, the horn plate 148 and the contact tip 152 come into contact with each other, and the horn sounds.

  The front end portion of the pin front 150 is a tapered tapered portion 150a, and a groove 150b is provided around the outer peripheral surface adjacent to the tapered portion 150a. The rear end side of the groove 150b is a straight shape portion 150c, and a flange portion 150d is provided on the rear end side of the straight shape portion 150c.

  The pin 145 has a male screw shaft portion 150e that protrudes rearward from the axial center portion of the flange portion 150d. The male screw shaft portion 150e is screwed onto the female screw of the cylindrical portion 151a of the pin rear 151, whereby the pin front 150 and the pin rear 151 are connected to form the pin 145.

  The pin rear 151 is slidably inserted into the guide column 153. A flange portion 153a is provided at the rear end of the guide column 153, and a claw portion 153b is provided at the front end portion. A vibration damper 154 is fitted on the guide column 153. The material of the damper 154 can be the same material as the damper 5 described above. One end surface of the damper 154 is in contact with the flange portion 153a. A washer 155 is disposed so as to overlap the other end surface of the damper 154. The washer 155 is locked to the claw portion 153b.

  Flange portions 154 a and 154 b are provided at both ends of the damper 154, and the flange portions 154 a and 154 b sandwich the peripheral edge portion of the pin holding hole 147, whereby the pin 145 is retained by the retainer 141 via the guide column 153 and the damper 154. Is held in. A rubber spacer 157 is provided so as to overlap the flange portion 153 a of the guide column 153.

  A coil spring 158 is interposed between the washer 155 and the flange portion 150d in a power storage state so as to surround the pin rear 151.

  In order to attach the airbag module 140 to the attachment portion 125, the pins 145 are respectively opposed to the insertion holes 126, the airbag module 140 is moved toward the attachment portion 125, and the pins 145 are inserted into the insertion holes 126. At this time, the horn plate 148 contacts the contact tip 152 of the pin 145, and the pin 145 is pushed directly by the horn switch plate 148 and moves forward.

  When the pin 145 moves forward, the tapered portion 150a comes into contact with the lock spring 127. When the lock spring 127 passes through the tapered portion 150 a, the lock spring 127 engages with the groove 150 b and the flange portion 150 d of the pin front 150 comes into contact with the peripheral portion on the inlet side of the insertion hole 126. Thereby, the pin 145 is firmly fixed to the attachment portion 125. When the hand is released from the airbag device 140, the retainer 141, the module cover 144, and the like are moved back to the occupant side by being pushed by the coil spring 158 to be in the state shown in FIG.

  In this airbag module 140, the diameter (outer diameter) of the flange portion 154b of each damper 154 is set to 20 mm or more, and the axial length of the damper 154 is set to 5 mm or more. The diameter of the circle is 80 mm or more, 110 mm or less, particularly 100 mm or less. Each damper 154 is arranged on the same circumference. As a result, as described above, the resonance frequency of the airbag module 140 is effectively suppressed to match the vibration frequency transmitted from the vehicle body side, and the hardness of the rubber material of the damper 154 can be easily adjusted. And cost can be reduced.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

[Example 1]
The inertance of the airbag module was measured using the steering wheel 1 shown in FIGS. Three dampers 5 were arranged at intervals of 120 ° on the circumference of a circle with a diameter of 100 mm centered on the center of gravity of the airbag module 3.

  The weight of the airbag module 3 was 1070 g. As the damper 5, an EPDM rubber material having a hardness of 33 according to a type A durometer in accordance with JIS K 6253 was used, and one having a shape as shown in FIG. 9 was used. The diameter (outer diameter) of the flange 52 of the damper 5 is 28 mm, the thickness of the flange 52 is 1.5 mm, the axial length of the damper 5 is 7.4 mm, the inner diameter of the body 51 is 11.8 mm, The outer diameter of the part 51 was 19.2 mm. The measurement results are shown in FIG.

[Comparative Example 1]
In Example 1, inertance was measured in the same manner as in Example 1 except that three dampers 5 were arranged on the circumference of a circle having a diameter of 120 mm. The measurement results are shown in FIG.

[Comparative Example 2]
In Example 1, inertance was measured in the same manner as in Example 1 except that the three dampers 5 were arranged on the circumference of a circle having a diameter of 140 mm. The measurement results are shown in FIG.

  As shown in FIG. 10, the resonance frequency at which the peak of inertance was 37 Hz in Example 1, 39 Hz in Comparative Example 1, and 43.25 Hz in Comparative Example 2. The graph shown in FIG. 11 shows an approximate curve obtained from the results of Example 1 and Comparative Examples 1 and 2, where the vertical axis represents the arrangement diameter of the damper 5 and the horizontal axis represents the resonance frequency. From this graph, it was confirmed that the resonance frequency decreased as the arrangement diameter of the damper 5 was reduced.

DESCRIPTION OF SYMBOLS 1 Steering wheel 2 Core metal part 3 Airbag module 4 Horn plate 5 Damper 6 Horn switch mechanism 7 Inflator 11 Wheel part 12 Spoke part 21 Shaft member 31 Retainer 32 Module cover 33 Claw part 45 Bending spring 46 Coil spring 53 Bush 54 Elastic body

Claims (5)

A steering wheel comprising a steering wheel body and an airbag module attached to the steering wheel body,
A steering wheel characterized in that a plurality of dampers for damping are arranged on the same circumference, and the diameter of this circle is 80 mm or more and 110 mm or less.   The steering wheel according to claim 1, wherein the diameter of the circle is 100 mm or less. In claim 1 or 2,
A plurality of shaft members are erected on the surface of the mandrel portion of the steering wheel body,
A plurality of openings through which the shaft member is inserted are formed in a horn plate that forms a horn switch mechanism with the cored bar,
The damper is disposed between the shaft member and the opening;
The steering wheel according to claim 1, wherein the airbag module is fixed to the horn plate. In claim 1 or 2,
A plurality of pins protruded from the back surface of the airbag module so as to advance and retract in the protruding direction,
The airbag module is attached by inserting the tip side of the pin into the insertion hole formed in the core part of the steering wheel body,
The rear end side of the pin is inserted through a guide column,
A steering wheel, wherein the guide column is held by a retainer of the airbag module via the damper.   The steering wheel according to any one of claims 1 to 4, wherein the damper includes ethylene propylene diene rubber.

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